Gas burner of high-velocity flame sheet type



J. H. FLYNN Sept. 11, 1962 GAS BURNER OF HIGH--VELOCITY FLAME SHEET TYPE Filed Nov. 12, 1959 u U I I 4/ M INVENTOR. 70/712 H F! 27 BY 2 United States Patent 3,053,316 GAS BURNER OF HIGH-VELOCITY FLAME SHEET TYPE John H. Flynn, 234 Elk Ave., New Rochelle, N.Y. Filed Nov. 12, 1959, Ser. No. 852,485 12 Claims. (Cl. 158116) This invention relates generally to burners of piloted utility flame type, and more particularly to burners of this type in which the utility flames combine to form a flame sheet.

The present invention is concerned with flame sheet burners of this type in which high-velocity flames from a large multitude of exclusively adjacent, relatively large main gas ports combine to form a continuous and sturdy flame sheet of most any required height and also heat intensity, with the high-velocity flames being maintained by pilot flames from an even larger multitude of lowvelocity gas ports which flank the main gas ports. The relatively large and closely adjacent main gas ports are supplied with combustible gas at substantially the full pressure of the supply gas admitted into the burner casing to achieve the required high velocity or drive of the flames thereat, while the closely adjacent low-velocity gas ports are not only smaller than the main gas ports but are supplied with combustible gas of considerably lower pressure than that of the supply gas in the burner casing in order to produce opposite pilot flame sheets of the bare drive and height required for safe maintenance of the high-velocity flames therebetween. To this end, the burner casing has customarily a slot in full communication throughout with the interior gas chamber thereof and grooves on opposite sides of the slot which are in communication with the gas chamber through spaced orifices of restricted size, with the main and low-velocity gas ports being usually formed by burner ribbons in the slot and grooves.

While the flames from these burners are satisfactory in most respects, they leave something to be desired in point of uniformity of the heat intensity of the high-velocity flame sheet throughout its expanse and also at its tip, as well as in point of evenness of the tip of the flame sheet throughout its expanse, wherefore the capacity as Well as uniformity of heat emission of this flame sheet is below optimum regardless of its application to matter to-beheated thereby in sweeping or tip-contact fashion. This is due to variations in maintenance of the high-velocity flames which, in turn, is caused by uneven pilot flames throughout the expanse of the respective piloting flame sheets which they form. The unevenness of the pilot flames, which sometimes is hardly perceptible but nevertheless real, is caused by uneven supplying of the lowvelocity ports with combustible gas, owing to the tendency of the gas admitted through the aforementioned spaced orifices into the burner grooves to flow in the latter in greater volume to the low velocity ports nearer to the respective orifices than to more distant low-velocity ports between successive orifices. Yet, any worthwhile alleviation of the uneven gas distribution to the low-velocity ports by providing a much larger number of correspondingly narrower spaced gas admission orifices to the burner grooves is not feasible, this in view of the fact that the restricted volumetric gas flow rate into the latter found most eflicient for piloting the main or high-velocity flames would require such small sizes of the larger number of orifices as to render their formation by drilling thoroughly impractical.

It is the primary object of the present invention to provide a burner of this type in which the capacity of the high-velocity flame sheet as well as the uniformity of its heat emission throughout its expanse are at an opti- 'ice mum, or near optimum, by providing for even and complete maintenance of the high-velocity flames, thereby also to achieve uniformity of the heat intensity, and evenness of the tip, of this high-velocity flame sheet throughout its expanse.

It is another object of the present invention to provide a burner of this type in which the aforementioned even and complete maintenance of the high-velocity flames is achieved by the pilot flames alone, by providing for fairly even distribution of combustible gas to the lowvelocity ports despite continued admission of the gas to the burner grooves exclusively through orifices of restricted size and without closer spacing or increase in number of these orifices.

It is a further object of the present invention to provide a burner of this type in which the aforementioned fairly even distribution of combustible gas to the low-velocity ports is achieved by placing into the path of the gas issuing from the spaced orifices into the burner grooves ohstructions which will divert and cause turbulence of the gas so that the same will be distributed in the burner grooves for supplying all the low-velocity ports fairly evenly.

Another object of the present invention is to provide a burner of this type in which the aforementioned obstructions in the path of gas issuing from the orifices into the burner grooves, rather than being special structural formations within the narrow confines of the customarily machined burner grooves, are readily machined lateral recesses in these burner grooves in line with the orifices, with the gas from the latter flowing directly into these recesses to be baflied thereby into the burner grooves proper in the aforementioned turbulent fashion to bring about the desired gas distribution in these burner grooves for fairly evenly supplying all the low-velocity ports.

A further object of the present invention is to provide a burner of this type in which the aforementioned gas orifices are advantageously provided, not directly in the burner casing as in most burners heretofore, but rather in screws received in holes drilled into the casing from the outside across the burner grooves and to the gas chamber thereof, with the holes being simply counterbored from the outside to the burner grooves and with the counterbores closed to the outside by plug-type nuts on the screwsto define the aforementioned lateral recesses in the burner grooves.

Other objects and advantages will appear to those skilled in the art from the following, considered in conjunction with the accompanying drawings.

In the accompanying drawings, in which certain modes of carrying out the present invention are shown for illustrative purposes:

FIGS. 1 and 2 are fragmentary side and top views of a burner embodying the present invention;

FIG. 3 is an enlarged cross-section through the burner taken substantially on the line 33 of FIG. 1;

FIG. 4 is a fragmentary transverse section through the burner taken substantially on the line 44 of FIG. 3; and

FIG. 5 is a fragmentary section through a burner embodying the present invention in a modified manner.

Referring to the drawings, the reference numeral 10 designates a burner having a longitudinal casing 12 with a gas chamber 14 across which extend in this instance reenforcing ribs 15 at relatively widely spaced intervals. The burner casing 12, with has a suitable inlet or inlets to its chamber 14 for a combustible gas, is provided with a longitudinal burner slot 16 which presently is throughout its expanse in open communication with the chamber 14, and is further provided with burner grooves 18 that extend parallel to and flank the burner slot 16 throughout its expanse. i

Received and suitably secured in the burner slot 16 are burner ribbons 20 of any suitable conventional type which define therein a multitude of high-velocity gas ports 22 of relatively large cross-sectional areas for high-velocity flames thereat, with these gas ports being so closely adjacent each other that the flames thereat combine to form a continuous high-velocity or utility flame sheet. Received and suitably secured in the burner grooves 18 are further burner ribbons 24 of any suitable conventional type which define therein low-velocity gas ports 26 of much smaller cross-sectional areas (FIGS. 2 and 3) for pilot flames which, in view of the close proximity of these gas ports, combine to form pilot flame sheets that maintain the utility flame sheet therebetween. The burner ribbons 24 are spaced from the bottoms 28 of the respective burner grooves 18 to define therein gas-distribution channels 30 which extend throughout the expanse of these grooves. The burner described so far may be entirely conventional and forms no part of the present invention except insofar as it enters into combination therewith.

Burners of this type usually have longitudinally spaced restricted gas passages leading from the chamber 14 to the channel parts 30 of the usually machined burner grooves 18 to conduct gas thereinto for sustaining the pilot flame sheets at the low-velocity ports 26. These restricted gas passages customarily open directly into the gas-distribution channels 30, with the result that the lowvelocity ports 26 are unevenly supplied with gas and the 'pilot flames thereat are uneven throughout the expanse of the pilot flame sheets which they form, all as previously explained. In accordance with the present invention, gas from the supply chamber 14 is conducted into the channels 30 in such manner that it will be distributed therein fairly evenly to all the low-velocity ports 26. To this end, gas from the supply chamber 14 is conducted, not directly into the distribution channels 30, but rather into side depressions or recesses 32 therein in which the gas is diverted into the channels proper in sufiiciently turbulent fashion to become distributed fairly evenly to all the lowvelocity ports 26. Gas under regulated pressure in the supply chamber 14 is conducted into the side recesses 32 in the channels 30 advantageously through restricted passages 34 in screw studs 36 which are threadedly received in longitudinally spaced bores 38 machined from the outside of the burner casing 12 transversely across the respective burner grooves 18 near their bottoms 28 and extending to the chamber 14 (FIGS. 3 and 4). These bores 38 are counterbored at 40 from the outside of the casing 12 at least to, and presently into the confines of, the respective burner grooves 30, to define the respective side recesses 32, the latter being closed to the outside of the casing 12 by plugs 42 and presently also by suitable sealing rings 44 seated in annular recesses 46 in the outside of the casing 12. The plugs 42 are presently threadedly received by the respective screw studs 36 for retaining their sealing rings 44 firmly seated in the annular recesses 46. The restricted passage 34 in each screw stud 36 is formed by an axial bore 48 therein and a diametrical cross bore 50 at the inner end of the latter which leads with its opposite ends into the respective side recess 32 a considerable distance from the place where the latter merges or opens into the associated channel 30. The outer end of each screw stud 36, which presently extends considerably beyond the associated plug 42, is provided with a suitable socket, presently a slot 52, for the reception of a screw driver with which to drive the screw stud into its tapped bore 38 as well as axially to adjust the same therein. Each plug 42 is provided with a socket, presently a slot 54, for the reception of a suitable tool with which to turn the plug on the associated stud 36 into and from its annular recess 46.

As shown in FIGS. 2 and 4, the screw studs 36 are arranged in spaced, and more particularly in equally spaced, fashion longitudinally of the respective gas distribution channels 30 with which they are associated, and their optimum spacing from each other is, of course, such as to achieve fairly even gas distribution to all low-velocity ports 26 in each burner groove 18 with the least number of these screw studs. Optimum spacing of the screw studs 36 from each other to this end varies quite understandably with many factors, such as the regulated pressure of the gas in the chamber 14 for an intended performance of the burner, the sizes of the passages 34 in the screw studs 36, the dimensions of the side recesses 32 in the channels 30, the depths and widths of the latter, and the dimensions of the low-velocity ports 26, just to mention a few of these factors. However, approximate optimum spacing of these screw studs 36 from each other for particular burners will readily be obtained at first from a few simple test arrangements and subsequently from experience.

In operation of the burner, gas admitted under suitable regulated pressure into the chamber 14 will flow at relatively high volumetric fiow rate into the burner slot 16 and through the high-velocity ports 22 substantially evenly throughout to sustain thereat high-velocity flames which form a utility flame sheet of desired considerable height and considerable drive. Gas from the chamber 14 will also be conducted through the passages 34 in the screw studs 36 into the side recesses 32 in the respective distribution channels 30, but at considerably reduced volumetric flow rate owing to the cross-sectional restrictions of the passages 34. The gas thus constantly discharged as continuous jets from the screw passages 34 into the associated side recesses 32 is directed primarily against opposite wall portions of the latter and deflected or redirected thereby in all directions, resulting in the flow of gas in these recesses 32 and from the latter into the associated distribution channels 30 at sufiiciently high turbulence to spread in these channels 30 longitudinally and widthwise thereof and become distributed substantially evenly to all lowvelocity ports 26 throughout. Hence, it is this turbulence of the gas at its discharge from the successive side recesses 32 in the respective channels 30 and entry into the latter which prevents the gas thereat from flowing predominantly to the nearest low-velocity ports and only superficially to the more remote velocity ports in regions midway between successive recesses 32, and instead compels the gas to spread out throughout the channels 30 sufliciently for its substantially even distribution to all low-velocity ports. To this end, all screw studs 36 are required to be received in their respective bores 38 in identical axially adjusted positions in order to locate the discharge ends of the passages 34 in these screw studs at identical depth levels in their respective recesses 32, and these screw studs are further required to be angularly adjusted so that their cross bores 50 extend longitudinally of the channels 30, as shown. These tasks are readily accomplished on driving the screw studs 36 into their respective tapped bores '38 to an appropriate depth easily gauged visibly from the outward projection of these studs, and by arranging the screwdriver slots 52 in the outer ends of these studs parallel to the longitudinal axis of the burner casing 12 (FIGS. 3 and 4). Moreover, a test performance of the burner will indicate instantaneously whether all screw studs are in identical axially adjusted positions or whether any of them require axial adjustment full-turnwise where unevenness of either pilot flame sheet is perceptible.

The aforementioned substantially even distribution of the turbulent gas in the channels 30 to all of the lowvelocity ports 26 makes for uniformity or evenness in all respects of the pilot flames thereat and, hence, of the pilot flame sheets throughout, and it is only by virtue of the evenness of these pilot flame sheets that the utility flame 'sheet which they maintain can and will also be even throughout.

The present invention, while securing the highly desirable functional advantage of remarkable evenness of the flames hitherto unattainable, is also of great structural simplicity. Thus, the screw studs 36, plugs 42 and sealing rings 44 are inexpensive automatic machine parts, and the multiple bores and counterbores 38, 40 and 46 of relatively large size in the burner casing 12 are even easier to machine than the previous restricted passages between the gas supply chamber and the burner grooves directly in the burner casing. In addition to that, the assembly of the screw studs 36 sealing rings 44 and plugs 42 with the burner casing, as well as correct adjustment of the screw studs axially and angularly, are extremely simple tasks as already explained hereinbefore.

Additional to the described normal identical adjustment of the screw studs, both angularly and axially, is the possibility of individual different adjustment, angularly or axially or both, of any screw stud to compensate for possible local abnormalities in the gas passage from the chamber to and through the low-velocity ports in nevertheless obtaining even pilot flames throughout.

FIG. 5 shows a slightly modified arrangement in which the screw studs 36a and plugs 42a are formed integrally in one piece, with the plugs 42a resting against somewhat compressible sealing rings 44a of copper or the like to permit tightening of the studs 36a with the screwdriver slots 52a finally remaining extended parallel to the longitudinal axis of the burner casing 12a.

The invention may be carried out in other specific ways than those herein set forth without departing from the spirit and essential characteristics of the invention, and the present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.

What is claimed is:

1. In a burner, the combination of a casing having a gas chamber, a longitudinal burner slot in open communication throughout with said chamber, longitudinal burner grooves open at the top to the outside of the casing and flanking said slot, first and second burner ribbon means in said slot and grooves defining therein highvelocity and low-velocity gas ports for utility and pilot flame sheets, respectively, with said second burner ribbon means being spaced from the bottoms of the respective grooves to define therein gas distribution channels, and sets of pairs of axially aligned larger and smaller bores in said casing extending transversely of said channels, with the pairs of bores of each set spaced longitudinally of a channel and with the larger and smaller bores of each set providing communication between the outside of the easing and the respective channel and between the latter and said chamber, respectively; plugs sealing from the outside of said casing said larger bores to form them into recesses open to the respective channels; and studs mounted in said smaller bores and extending into the associated recesses with clearance therefrom and having passages conducting gas from said chamber into said recesses for its diversion thereby and turbulent flow into the respective channels and ensuing substantially even gas delivery to all lowvelocity ports.

2. In a burner, the combination of a casing having a gas chamber, a longitudinal burner slot in open communication throughout with said chamber, longitudinal burner grooves open at the top to the outside of the casing and flanking said slot, first and second burner ribbon means in said slot and grooves defining therein highvelocity and low-velocity gas ports for utility and pilot flame sheets, respectively, with said second burner ribbon means being spaced from the bottoms of the respective grooves to define therein gas distribution channels, and sets of pairs of axially aligned larger and smaller bores in said casing extending transversely of said channels, with the pairs of bores of each set spaced longitudinally of a channel and with the larger and smaller bores of each set providing communication between the outside of the casing and the respective channel near its bottom and between the latter channel and said chamber, respectively;

plugs sealing from the outside of said casing said larger bores to form them into recesses open to the respective channels; and screw studs threadedly received in said smaller bores and extending into the associated recesses with clearance therefrom and having passages terminating within said recesses to conduct thereinto gas from said chamber for its diversion and turbulent flow into the respective channels and ensuing substantially even gas delivery to all low-velocity ports.

3. The combination in a burner as set forth in claim 2, in which said studs extend in sealed fashion through the respective plugs to the outside of the casing there to be accessible for turning.

4. The combination in a burner as set forth in claim 2, in which said larger bores have counterbores from the outside of the casing in which the respective plugs are seated in sealing fashion, and said studs extend through and are threadedly received by the respective plugs to hold the latter seated in their counterbores.

5. The combination in a burner as set forth in claim 2, in which said larger bores have counterbores from the outside of the casing in which the respective plugs are seated in sealing fashion, and said studs extend through the respective plugs to the outside of the casing there to be accesible for turning, with said plugs being threadedly received by the respective studs to be held thereby seated in their counterbores.

6. The combination in a burner as set forth in claim 2, in which said passage in each stud is formed by an axial passage part therein open at one end to said chamber and a transverse through-passage part at the other end of said axial passage part and open to the respective recess, and each stud extends in sealed fashion through the respective plug to the outside of the casing there to be accessible to a tool with which to turn said stud.

7. The combination in a burner as set forth in claim 2, in which said larger bores have counterbores from the outside of the casing in which the respective plugs are seated in sealing fashion, said passage in each stud is formed by an axial passage part therein open at one end to said chamber and a transverse through-passage part at the other end of said axial passage part and open to the respective recess, each stud extends through the respective plug to the outside of the casing and is there formed with a slot for the reception of a tool with which to turn said stud, and each plug is threadedly received by the respective stud and has a slot accessible from the outside of the casing to a tool with which to turn said plug on its stud into and from seating engagement with its counterbore.

8. The combination in a burner as set forth in claim 2, in which said larger bores have counterbores from the outside of the casing in which the respective plugs are seated in sealing fashion, said studs are integral with the respective plugs, and said plugs are formed with a slot for the reception of a tool with which to turn them and their studs.

9. The combination in a burner as set forth in claim 2, in which said larger bores have counterbores from the outside of the casing in which the respective plugs are seated in sealing fashion, said passage in each stud is formed by an axial passage part therein open at one end to said chamber and a transverse through-passage part at the other end of said axial passage part and open to the respective recess, each stud extends through the respective plug to the outside of the casing and is in its outer end formed with a slot extending parallel to said transverse throughpassage part therein and adapted for the reception of a screwdriver with which to turn said stud, and each plug is threadedly received by the respective stud and has a slot accessible from the outside of the casing to a tool with which to turn said plug on its stud into and from seating engagement with its counterbore.

10. The combination in a burner as set forth in claim 2, in which said larger bores have counterbores from the outside of the casing with compressible sealing rings seated in said counterbores and said plugs seated on said sealing rings, each stud is formed integrally with the respective plug and said passage in each stud is formed by an axial passage part therein open at one end to said chamber and a transverse through-passage part at the other end of said axial passage part and open to the respective recess, and each plug has in its outer end a slot extending parallel to said through-passage part in its stud and adapted for the reception of a screwdriver with which to turn said plug and stud.

11. In a burner, the combination with a casing having a gas chamber and a longitudinal burner slot in open communication throughout with said chamber and burner ribbon means in said slot defining therein high-velocity gas ports for a utility flame sheet, of means providing in said casing longitudinal burner grooves flanking said slot and having bottoms and oposite side walls and being open at the top to the outside of the casing; other burner ribbon means in said grooves defining therein low-velocity gas ports for pilot flame sheets to maintain the utility flame sheet therebet-Ween, said other burner ribbon means being spaced from the bottoms of the respective grooves to define therein gas distribution channels, With the side Walls of said grooves most remote from said burner slot being formed within the height of said channels with longitudinally spaced depressions; and conduit means in said casing providing passages of restricted cross-sectional areas and extending from said chamber across the entire width of each of said channels and into the confines of said depressions, with said passages and depressions forming the sole communication within said casing between said chamber and channels and said passages conducting all gas flowing therethrough into said depressions for diversion by the latter into sufiiciently turbulent flow into said said slot and grooves defining therein high-velocity and low-velocity gas ports for utility and pilot flame sheets, respectively, with said second burner ribbon means being spaced from the bottoms of the respective grooves to define therein gas distribution channels, and longitudinally spaced recesses in the side Walls of said grooves most remote from said burner slot and within the height of said channels, said recesses being formed by bores from the outside of the casing to and transversely of the respective adjacent grooves and sealing plugs in the outer ends of said bores; and conduit means in said casing providing passages of restricted cross-sectional areas and extending from said chamber across the entire width of each of said channels and into the confines of said recesses, with said passages and recesses forming the sole communication within said casing between said chamber and channels and said passages conducting all gas flowing therethrough into said recesses for diversion by the latter into sufliciently turbulent flow into said channels to obtain therein substantially even gas delivery to all low-velocity ports.

References Cited in the file of this patent UNITED STATES PATENTS 1,105,031 Hagemeyer July 28, 1914 1,907,734 Butz May 9, 1933 2,647,569 Flynn Aug. 4, 1953 

